You didn't attach any photos but in the absence of them, I believe that you may have Apple Scab. We are seeing a lot of it this year and getting many questions.

Below is some information on Fire Blight and Apple Scab that should help you. Read them over and look at what symptoms best fit your trees. Fire Blight occurs more during hot dry spells and we have been very wet this year. Neither should kill your tree unless it is affected for a few years in a row. Below is the response I have been sending to many folks this year.

You probably have Apple Scab. We are getting a lot of questions about it this year. It will not kill your tree unless it suffers for many years in a row.

Be sure to clean up all fallen leaves and debris this summer and do a thorough clean up in the fall because the fungi will over-winter in the debris.

Dispose of the leaves in your municipal compost. Do not compost these at home as your home compost will not get hot enough to kill the pathogens.

https://extension.umn.edu/plant-diseases/fire-blight

https://extension.umn.edu/plant-diseases/apple-scab

https://hort.extension.wisc.edu/articles/applescab/